**The pin.** Pin a TAG, never a bare sha. A sha reachable only from an auto/*
branch is orphaned when that branch is deleted or -- worse -- squash-merged,
because squash creates new commits: main looks like it contains the work while
the pin becomes unreachable and this project stops building for a fresh
checkout, silently, at their build. formats-pin-2026-08-29 exists for the
current state.
Also says plainly why NOT to float to a branch, which was the tempting fix:
Cargo resolves a git dependency once and writes the sha into Cargo.lock, so
floating gives staleness you cannot see instead of staleness you can read.
push-work now pushes --follow-tags so annotated tags travel with the branch.
**Audio.** docs/AUDIO-VERIFICATION.md separates three questions that were being
asked as one: is the transcode faithful (no engine, no device -- a file-vs-file
difference measurement), does Godot route it (AudioEffectRecord on the Master
bus writes a WAV from a headless run), and what does the GAME play (a PulseAudio
null sink, which needs a rebuild).
It leads with the three ways the fidelity measurement lies, because all three
were hit on the first attempt and each produces a confident wrong number rather
than an error: unaligned subtraction, mismatched channel layouts, and probing a
file another process is still writing.
The 5.1 disc fact deliberately is NOT copied here -- it lives in the RE corpus
at docs/re/structures/movie-audio-channels.md and is linked, so there is one
copy to keep true rather than two that drift. Same reason HANDOFF is a summary
with links.
The downmix itself stays flagged as an unmade decision, not quietly resolved.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
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